High pressure over the North pacific is a Feature of Summer . which ofter begins on the 5th of July.. Ride start: North To South.
winds tend to come behind you..

You will find Hundreds of other cyclists doing that route during that season. https://www.oregon.gov/ODOT/HWY/BIKE..._route_map.pdf

I live here . Columbia River is 2 blocks from my front door..


Here is NOAA weather for the area , to Book mark and follow .. National Weather Service

put other town names in for other areas.